Generally, a power converter contains power electronic devices, for example, metal oxide semiconductor field-effect transistors (MOSFETs) or insulated gate bipolar transistors (IGBTs), and one or more controllers. The power electronic devices function as controlled switches, while the controllers produce the required control signals. A gate driver is an interface electronic circuit between a power electronic device and a controller. The gate driver may accept a logic input (i.e., an input digital signal) from the controller and correspondingly produce an output to drive the gate of the power electronic device (i.e., an output gating signal). The gate driver may fulfill several purposes, one of which is voltage shifting. In practice, the voltage level of the controller's digital signal may be different from what is required to drive the power electronic device. For example, MOSFETs generally require gate voltages more than 6V, while many controllers produce digital outputs at 1.8, 3.3, or 5V. Therefore, the gate driver may serve as a voltage shifter or booster to match different voltage levels between controller(s) and power electronic devices.
A gate driver may employ multiple bias voltages to implement the level shifting. For example, the gate driver may use a first 5V bias voltage to interface with a controller, and a second 10V bias voltage to provide a gating signal for a power electronic device. Alternatively, the controller itself may include a first bias voltage to bring its digital outputs to a voltage level compatible with the gate driver, while the gate driver may use a second bias voltage to provide an appropriate gating signal for the power electronic device. Nonetheless, the power converter, as a whole, may still have to employ multiple bias voltages to accommodate the voltage requirements of different components. These individual bias voltages have typically been provided by separate, dedicated power supply circuits. All this may create a design complexity, which may impact the power converter's reliability, cost, packaging, and efficiency. Therefore, what is needed is a gate driver with simplified requirements for bias voltages but still capable of providing voltage boosting.